From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f69.google.com (mail-oi0-f69.google.com [209.85.218.69]) by kanga.kvack.org (Postfix) with ESMTP id C73E76B06C2 for ; Fri, 11 May 2018 15:10:41 -0400 (EDT) Received: by mail-oi0-f69.google.com with SMTP id 5-v6so3426421oiq.6 for ; Fri, 11 May 2018 12:10:41 -0700 (PDT) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id v20-v6si1368917ote.289.2018.05.11.12.10.40 for ; Fri, 11 May 2018 12:10:40 -0700 (PDT) From: Jean-Philippe Brucker Subject: [PATCH v2 34/40] ACPI/IORT: Check ATS capability in root complex nodes Date: Fri, 11 May 2018 20:06:35 +0100 Message-Id: <20180511190641.23008-35-jean-philippe.brucker@arm.com> In-Reply-To: <20180511190641.23008-1-jean-philippe.brucker@arm.com> References: <20180511190641.23008-1-jean-philippe.brucker@arm.com> Sender: owner-linux-mm@kvack.org List-ID: To: linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, iommu@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org Cc: joro@8bytes.org, will.deacon@arm.com, robin.murphy@arm.com, alex.williamson@redhat.com, tn@semihalf.com, liubo95@huawei.com, thunder.leizhen@huawei.com, xieyisheng1@huawei.com, xuzaibo@huawei.com, ilias.apalodimas@linaro.org, jonathan.cameron@huawei.com, liudongdong3@huawei.com, shunyong.yang@hxt-semitech.com, nwatters@codeaurora.org, okaya@codeaurora.org, jcrouse@codeaurora.org, rfranz@cavium.com, dwmw2@infradead.org, jacob.jun.pan@linux.intel.com, yi.l.liu@intel.com, ashok.raj@intel.com, kevin.tian@intel.com, baolu.lu@linux.intel.com, robdclark@gmail.com, christian.koenig@amd.com, bharatku@xilinx.com, rgummal@xilinx.com, lorenzo.pieralisi@arm.com, hanjun.guo@linaro.org, sudeep.holla@arm.com Root complex node in IORT has a bit telling whether it supports ATS or not. Store this bit in the IOMMU fwspec when setting up a device, so it can be accessed later by an IOMMU driver. Use the negative version (NO_ATS) at the moment because it's not clear if/how the bit needs to be integrated in other firmware descriptions. The SMMU has a feature bit telling if it supports ATS, which might be sufficient in most systems for deciding whether or not we should enable the ATS capability in endpoints. Cc: lorenzo.pieralisi@arm.com Cc: hanjun.guo@linaro.org Cc: sudeep.holla@arm.com Signed-off-by: Jean-Philippe Brucker --- drivers/acpi/arm64/iort.c | 11 +++++++++++ include/linux/iommu.h | 4 ++++ 2 files changed, 15 insertions(+) diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c index 7a3a541046ed..4f4907e58cc8 100644 --- a/drivers/acpi/arm64/iort.c +++ b/drivers/acpi/arm64/iort.c @@ -1004,6 +1004,14 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) dev_dbg(dev, "dma_pfn_offset(%#08llx)\n", offset); } +static bool iort_pci_rc_supports_ats(struct acpi_iort_node *node) +{ + struct acpi_iort_root_complex *pci_rc; + + pci_rc = (struct acpi_iort_root_complex *)node->node_data; + return pci_rc->ats_attribute & ACPI_IORT_ATS_SUPPORTED; +} + /** * iort_iommu_configure - Set-up IOMMU configuration for a device. * @@ -1039,6 +1047,9 @@ const struct iommu_ops *iort_iommu_configure(struct device *dev) info.node = node; err = pci_for_each_dma_alias(to_pci_dev(dev), iort_pci_iommu_init, &info); + + if (!err && !iort_pci_rc_supports_ats(node)) + dev->iommu_fwspec->flags |= IOMMU_FWSPEC_PCI_NO_ATS; } else { int i = 0; diff --git a/include/linux/iommu.h b/include/linux/iommu.h index bcce44455117..d7e2f54086e4 100644 --- a/include/linux/iommu.h +++ b/include/linux/iommu.h @@ -655,12 +655,16 @@ struct iommu_fwspec { const struct iommu_ops *ops; struct fwnode_handle *iommu_fwnode; void *iommu_priv; + u32 flags; unsigned int num_ids; unsigned int num_pasid_bits; bool can_stall; u32 ids[1]; }; +/* Firmware disabled ATS in the root complex */ +#define IOMMU_FWSPEC_PCI_NO_ATS (1 << 0) + int iommu_fwspec_init(struct device *dev, struct fwnode_handle *iommu_fwnode, const struct iommu_ops *ops); void iommu_fwspec_free(struct device *dev); -- 2.17.0